Electomagnetic oscillation in lc circuit

In summary, when a charged capacitor is connected to a coil, the current will oscillate back and forth between the two, causing the capacitor to be re-charged and creating electromagnetic oscillations in the circuit.
  • #1
amjad-sh
246
13
Hi,

We know that when we connect a charged capacitor to a coil, the capacitor will discharge in the coil that means that the current will flow in the circuit in decreasing manner with respect to time .So an emf will be created in a way that oppose the decrease.
Bin will has the same direction of Bext that is due to the movement of current in the coil.
Bin is due to an induced current right?
But the induced current will contribute in discharging the capacitor,when the capacitor is completely discharged the current must be zero in that instant and so Bext is zero.
My question is why the capacitor is charged again from where the current came?
I think the energy of the coil is consumed during the charging of the capacitor not after the capacitor is charged, since Bind is created by the coil during the time of charging of the capacitor ?
I'm really confused , this is due to the big misunderstanding of the concept.
I would appreciate it if anybody can explain briefly what is happening and how electromagnetic oscillation occurs in lc circuits
 
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  • #2
. Thanks in advance!When a charged capacitor is connected to a coil, current flows from the capacitor and induces an emf in the coil that opposes the decrease in current. This emf then causes the current to oscillate back and forth between the capacitor and the coil. After the capacitor is discharged, the energy stored in the coil is used to re-charge the capacitor, causing the oscillations to continue. The oscillations will persist until all of the energy stored in the coil is dissipated as heat.
 

FAQ: Electomagnetic oscillation in lc circuit

1. What is an LC circuit?

An LC circuit is a type of electrical circuit that consists of an inductor (L) and a capacitor (C) connected in series or parallel. This circuit is commonly used in electronics to generate or filter specific frequencies of electrical signals.

2. What is electromagnetic oscillation?

Electromagnetic oscillation, also known as electromagnetic resonance, is the process in which an electrical circuit exhibits a periodic back-and-forth movement of energy between the electric and magnetic fields. This phenomenon is essential in the operation of many electronic devices, including LC circuits.

3. How does an LC circuit produce oscillations?

When an LC circuit is charged, the electric field of the capacitor and the magnetic field of the inductor are at maximum strength. As the energy oscillates between the two fields, the voltage across the capacitor and the current through the inductor also oscillate. This creates a continuous cycle of energy exchange, resulting in electromagnetic oscillation.

4. What is the resonant frequency of an LC circuit?

The resonant frequency of an LC circuit is the frequency at which the circuit naturally oscillates when charged. It is determined by the values of the inductor (L) and capacitor (C) and can be calculated using the formula f=1/(2π√(LC)). At the resonant frequency, the circuit has the maximum amplitude of oscillation.

5. What are some practical applications of LC circuits?

LC circuits have numerous practical applications, such as in radio and television receivers, electronic filters, and oscillators. They are also used in wireless charging technology, RFID systems, and electronic ballasts for fluorescent lights. Additionally, LC circuits play a crucial role in the functioning of electronic devices such as computers, smartphones, and televisions.

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